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Exploring possibilities with simple indexed fields

Database records and formlets and optionally populated records can be neatly all represented with the same data type when the fields are all indexed.

class Indexed i a where
  type Index i (a :: *)

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Common

export OPT=/opt
export BUILDS=/some/where/mini_linux
mkdir -p $BUILDS

Linux kernel

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Basic unit type:

λ> replTy "()"
() :: ()

Basic functions:

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-- λ> eval (A (L (\(C i) -> C (i * 2))) (C 2))
-- 4

{-# LANGUAGE GADTs #-}

data E a where
  C :: a -> E a
  L :: (E a -> E b) -> E (a -> b)
  A :: E (a -> b) -> E a -> E b

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Typing Haskell in Haskell

MARK P. JONES

Pacific Software Research Center

Department of Computer Science and Engineering

Oregon Graduate Institute of Science and Technology

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Type Inference: Various Designs

I'm exploring the right data types for writing a type inference with higher kinds and poly types.

Putting more things in the type system can force you to think about more things, but it also can make it harder and more verbose to write and read algorithms.

• This one implements a fairly good type inferer, with a free monad, but kinds are not enforced, and forall/schemes are not considered atll.
• This one pushes kinds and generic vars into the type system with a nested tuples approach
• This one borrows from Oleg's typed eval, but doesn't actually implement any hard things yet.

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{-# LANGUAGE NamedFieldPuns #-}

-- The Expression Problem and my sources:
-- http://stackoverflow.com/questions/3596366/what-is-the-expression-problem
-- http://blog.ontoillogical.com/blog/2014/10/18/solving-the-expression-problem-in-clojure/
-- http://eli.thegreenplace.net/2016/the-expression-problem-and-its-solutions/
-- http://www.ibm.com/developerworks/library/j-clojure-protocols/


-- To begin demonstrating the problem, we first need some

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output/

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module Printf

%default total

-- Formatting AST.
data Format
  = FInt Format
  | FString Format
  | FOther Char Format
  | FEnd

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Idea: A web frontend for Emacs via CodeMirror

This is a discussion/thought-process document with my ideas that I've been adding to recently.

Motivation

Why a web frontend for Emacs?

1. A web frontend would benefit from being cross-platform in the sense